Re: [libvirt] [PATCH v2] storage: Disallow usage of the HBA for a fc_host backing
On Tue, Jul 25, 2017 at 07:36:48AM -0400, John Ferlan wrote:
On 07/25/2017 03:45 AM, Erik Skultety wrote:
>> +/**
>> + * @name: Name from a wwnn/wwpn lookup
>> + *
>> + * Validate that the @name fetched from the wwnn/wwpn is a vHBA and not
>> + * an HBA as that should be a configuration error. It's only possible to
>> + * use an existing wwnn/wwpn of a vHBA because that's what someone would
>> + * have created using the node device create functionality. Using the
>> + * HBA "just because" it has a wwnn/wwpn and the characteristics of
a
>> + * vHBA is just not valid
>> + *
>> + * Returns the @scsi_host_name to be used or NULL on errror
s/errror/error
...
>> @@ -275,6 +316,7 @@ createVport(virConnectPtr conn,
>> virStorageAdapterFCHostPtr fchost)
>> {
>> char *name = NULL;
>> + char *scsi_host_name = NULL;
>> virStoragePoolFCRefreshInfoPtr cbdata = NULL;
>> virThread thread;
>> int ret = -1;
>> @@ -288,6 +330,9 @@ createVport(virConnectPtr conn,
>> * this pool and we don't have to create the vHBA
>> */
>> if ((name = virVHBAGetHostByWWN(NULL, fchost->wwnn, fchost->wwpn)))
{
>> + if (!(scsi_host_name = checkName(name)))
>> + goto cleanup;
>
> Ok, so I learn from my mistakes, do you plan on building upon this in the
> foreseeable future with a follow-up series you haven't sent yet, but have on a
> local branch? Because if not, I don't really see a point in returning a string
> which only gets free'd on the function exit - checkName should probably become
> something like "isVHBA" and return boolean. And even if you do have a
follow-up
> on a local branch, I still think that converting the return value should be
> part of that series, solely because until then, @scsi_host_name wouldn't have
> any meaning.
>
> Erik
>
No this is it - I want to stop thinking about NPIV for a while... I
returned the 'scsi_host_name' string because in my mind I had passed it
to checkParent, but apparently I didn't do that, sigh.
Does that make more sense now?
Indeed, to be honest I missed the connection between name and scsi_host_name
and thought, yeah ok makes sense (probably have seen quite a lot NPIV lately
myself)....now that I see it a bit more clearly, it still left me wondering if
it wouldn't make more sense to move the scsi_host_name formatting part to
createVport (you free it here after all) right after you pass @name to
checkName/isVHBA (whatever we settle on):
- you don't need to format it prior to your checkName, since backwards
compatibility takes care of eating "hostX" nicely
- you also don't need to report any error when virSCSIHostGetNumber fails,
since one gets formatted already and it didn't bring much value
-> then, right after that call you actually format the "scsi_" name since
you
really need it to traverse the list of devices and find the parent in
checkParent.
Erik
John